﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace OAuthAccess
{
    internal static class StringExtension
    {
        internal static string OAuthPercentEncode(this string s)
        {
            string unreserved = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_.~";
            StringBuilder result = new StringBuilder();
            byte[] data = Encoding.UTF8.GetBytes(s);
            foreach (byte b in data)
            {
                if (b < 0x80 && unreserved.IndexOf((char)b) != -1)
                    result.Append((char)b);
                else
                    result.Append('%' + String.Format("{0:X2}", (int)b));
            }
            return result.ToString();
        }

        internal static string UrlEncode(this string s)
        {
            StringBuilder rt = new StringBuilder();
            foreach (byte i in Encoding.UTF8.GetBytes(s))
                if (i == 0x20)
                    rt.Append('+');
                else if (i >= 0x30 && i <= 0x39 || i >= 0x41 && i <= 0x5a || i >= 0x61 && i <= 0x7a)
                    rt.Append((char)i);
                else
                    rt.Append("%" + i.ToString("X2"));
            return rt.ToString();

        }

        internal static List<Parameter> ParseParameters(this string s)
        {
            List<Parameter> result = new List<Parameter>();
            string[] keyAndValues = s.Split('&');
            
            foreach (string keyAndValue in keyAndValues)
            {
                result.Add(
                    new Parameter() { Key = keyAndValue.Split('=')[0], Value = keyAndValue.Split('=')[1] }
                    );
            }

            return result;

        }
    }
    
}
